Many times it is desirable to form a strand consisting of a very large number of filaments. Generally, a number of small strands consisting of a plurality of filaments in each are combined in a roving process to produce a single large strand or roving of a large number of filaments. To accomplish this, filaments are pulled from a feeder and wound upon a forming tube being rotated by a winder to form a subpackage. Such subpackages are positioned as a group to remove each of the strands therefrom to combine the substrands into a larger strand by the action of yet another winder as is known in the art. Or the combined strand can be pulled by the action of a cot wheel and a chopper to deliver a large number of continuous filaments to be cut into discrete segments.
Generally, a reduction in the equipment utilized in the steps employed in producing such a strand containing a large number of filaments can lead to improved efficiencies and reduced costs. This is especially practical wherein all of the filaments can be attenuated by the action of a single attenuation means located on a single level of a forming room.
Systems for producing chopped glass segments from a plurality of spaced apart bushings have been employed before. But, due to the orientation of the bushings, coating applicators, gathering shoes, idler rolls, and scrap pull rolls and the like, a strand break out could disrupt at least a portion of the remaining forming operation, if an intermediate forming section was disrupted.
Furthermore, in the production of discrete fibers or chopped strand, it is desirable to concomitantly pull continuous glass fibers from a plurality of spaced apart feeders adapted to supply a strand or plurality of strands to the chopper wherein the cot wheel of the chopper acts as a pull wheel to attenuate the streams of molten material issuing from the feeders into filaments. In drawing the filaments from a plurality of bushings to be advanced through the chopper, it is possible to maintain production from a number of bushings even though one or more bushings may be disrupted. With the bushings and other apparatus oriented to provide continuous operation in spite of a disruption of one or more bushings, it is desirable to have the operator restart the disrupted feeder to again supply filaments to the chopper in the absence of disrupting the other bushings.
To accomplish this, the filaments must be continuously attenuated from all bushings still in operation. Thus, the chopper cannot be stopped. However, with high speed operations it is difficult and sometimes undesirable to try to rethread the chopper at high speed. Therefore, the rotational speed of the chopper must be reduced to allow the operator to rethread the strand but yet maintain a speed sufficient to attenuate filaments from the other bushings to prevent substantial disruptions therein.
At the reduced speed, however, the discrete fibers formed may not be of the proper size or quality desired. To insure that the secondary or waste discrete fibers are not placed in the receptacle containing the desired chopped strand/fibers it is necessary that the secondary fibers be directed elsewhere.